Fuels or oil frequently contain water, which can lead to malfunctions in the machines operated with the fuel or oil, in particular internal combustion engines. As a result, water separating systems having a water separator have been used for some time to separate or remove the water contained in the fuel or oil. Depending upon the design, the water separators include a support tube, which is provided with an end plate at both ends. Arranged inside the support tube is a screen tube, which together with the support tube delimits a water separating gap. The water separating gap is used for the gravity-related deposition of the water contained in the fuel or oil and is fluidically connected at one end to a water outlet arranged at the lower end of the water separator.
Such a water separator is known for example from DE 10 2010 030 987 A1.
When the water separator is in operation, the separated water flows as a rule, due to gravity, from the water separator into a water collection chamber arranged beneath the water separator. The water collection chamber can be formed for example by the separator housing of the water separating system. When a maximum water fill level is reached within the water collection chamber, the accumulated water must be removed from the water collection chamber however. For this purpose, the housing of the water separating system can include for example a base-side water drain device, in the simplest case structurally, a so-called drain screw. In practice, it has been proven in tight installation conditions, such as in the engine compartment of a motor vehicle, if the water separator itself is provided with a water discharge device. In this way, the water accumulated in the water collection chamber can be discharged as needed from the water collection chamber via the water separator in an upward direction.
A water separator having such an integrated water discharge device is known from DE 10 2009 058 812 A1. The water discharge device of the water separator has an inlet or outlet opening, which is arranged eccentrically on the water outlet side, i.e., in the installed state of the water separator on the lower end of the water separator and at an axial distance from the second end plate. An outlet opening of the water discharge device is associated, in the installed state of the water separator, with the upper end plate of the water separator and arranged eccentrically to the longitudinal axis of the water separator. A connection of the water discharge device to a water discharge connecting piece of a separator housing is thereby made difficult. In addition, the water separator requires a relatively large installation space due to the structural design of the water separating device thereof.
EP 2 135 659 A1 discloses another water separator for water contained in fuel. The water separator has a water separating device, which is upstream from a particle filter medium in the flow direction of the fuel and which is therefore arranged on the so-called raw or dirty side of the water separator. The water separator consequently has a less efficient water separating capacity.